<!DOCTYPE html>
<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        * {
            margin: 0;
            padding: 0;
            list-style: none;
        }

        .box {
            width: 90%;
            margin: 0 auto;
            overflow: hidden;
            position: relative;
        }

        ul {
            display: flex;
            position: relative;
            left: 0;
            transition: left .2s linear;
        }

        ol {
            display: flex;
            position: absolute;
            bottom: 10px;
            width: 100%;
            left: 0;
            justify-content: center;
        }

        ol>li {
            width: 10px;
            height: 10px;
            background-color: #fff;
            margin: 0 8px;
        }

        ol>li.action {
            background-color: black;
        }

        img {
            border-radius: 5px;
            display: block;
        }

        .boximg {
            width: 90vw;
        }
    </style>
</head>

<body>
    <div class="box">
        <ul>
            <!-- <li>
                <img src="" alt="">
            </li> -->
        </ul>
        <ol>
            <!-- <li></li> -->
        </ol>
    </div>
    <script>
        var image = ["https://m15.360buyimg.com/mobilecms/s1062x420_jfs/t1/33428/39/16450/106681/6311cad7Ef9b3d856/f10720b7f8f38937.jpg!cr_1053x420_4_0!q70.jpg",
            "https://m15.360buyimg.com/mobilecms/jfs/t1/3230/40/20384/44107/62daf2d9E5c5e0e55/03ab360c40ddc266.jpg!cr_1125x449_0_166!q70.jpg",
            "https://m15.360buyimg.com/mobilecms/jfs/t1/110775/22/28940/94917/62e5bc6dE569b2244/5d14fc9f06d87341.jpg!cr_1125x449_0_166!q70.jpg"];


        var ul = document.querySelector('.box > ul');
        var ol = document.querySelector('.box > ol');
        var box = document.querySelector('.box');

        var str = '', str1 = '';
        for (var k = 0; k < image.length; k++) {
            // console.log(image[k]); 得到三张图片的遍历
            str += `<li><img class = 'boximg' src="${image[k]}" alt=""> </li>`;
            if (k == 0) {
                str1 += `<li class='action'></li>`
            } else {
                str += `<li></li>`
            }
            // console.log('-----', str); 
        }

        ul.innerHTML = str;
        ol.innerHTML = str1;
        // 给标签设置初始样式
        ul.style.width = image.length * box.offsetwidth + "px";


        // 页面加载完成后默认显示第0张
        // 记录当前显示图片（li）的索引值（点击下一张或者上一张都是由当前显示的图进行上一张或下一张）

        var i = 0;
        var ollis = document.querySelectorAll('.box > ol > li')

        // 点击下一张实现ul的left移动到下一张li的位置
        // 在box上 按下 抬起 记录按下时与抬起时手指触碰的位置
        // 根据两个x判断手指是向左滑还是向右滑了

        var start = 0;
        box.ontouchstart = function (e) {
            start = parseInt(e.touches[o].clientX);
        }
        box.ontouchend = function (e) {
            var end = parseInt(e.changeTouches[0].clientX);
            if (start > end && start - end >= 50) {
                i++;
                if (i == image.length) i = image.length - 1;
            } else if (end - start >= 50) {
                i--;
            }
        }
    </script>
</body>

</html>